HI Ken,
I downloaded the resized jpg you posted up here and fed it into AT with Settings as per screenshot below.
It prompts the same error message (i had to kill the process in the end):
2017-09-11 20:33:26,371 - astrotortilla - INFO - Connecting to camera...
2017-09-11 20:33:26,372 - astrotortilla - INFO - Exposing: 80.00 seconds
2017-09-11 20:33:28,313 - astrotortilla - INFO - Reading image from camera
2017-09-11 20:33:28,316 - astrotortilla - INFO - Solving...
2017-09-11 20:33:28,420 - astrotortilla - INFO - 0 [main] bash 8036 find_fast_cwd: WARNING: Couldn't compute FAST_CWD pointer. Please report this problem to
2017-09-11 20:33:28,526 - astrotortilla - INFO - the public mailing list
cygwin@cygwin.com
2017-09-11 20:33:28,829 - astrotortilla - INFO - Reading input file 1 of 4: "-"...
2017-09-11 20:38:29,773 - astrotortilla - INFO - pnmfile: Error reading magic number from Netpbm image stream. Most often, this means your input file is empty.
2017-09-11 20:38:29,776 - astrotortilla - INFO - No solution in 301.5s